Explain Programme Evaluation and Review Technique.

Programme Evaluation and Review Technique (PERT): It is a technique used for scheduling and controlling the projects whether activities are subject to considerable degree of uncertainty in the performance time. Initially it was used with the US Ballistic Fleet Missile Project of the US Government in designing and producing main weapon systems for the US Military Establishment. It is because unlike CPM, that is determinative, the orientation of PERT is probabilistic and its application is mostly for Research and Development projects. Programme evaluation and review technique is used to evaluate the variance in project duration and also to find out the probability of completing a project by a specified date. Unlike CPM, that uses only one time estimation for each activity; PERT uses three time estimates, which are: optimistic time, most probable time and pessimistic time. The fundamental tool used in PERT technique is the network or flow plan. Network contains series of related events and activities. Therefore the network drawn shows how different activities of a project depends upon each other and that certain activities have to be completed before another can start.